Medium voltage (MV) current-limiting fuses are widely used in the electrical utility and switchgear manufacturing industries for voltages typically in the range of 1 kV to 72.5 kV. The main function of such fuses is to protect electrical apparatus (e.g., distribution transformers, motors, and capacitor banks) against overcurrents.
Existing MV current-limiting fuses have been observed to be too slow to activate in certain situations. In this regard, there is a need in various applications for an MV current-limiting fuse that can more quickly activate at low current faults and can activate at load currents in response to an external condition at load currents.
The present invention provides a MV current-limiting controllable fuse that address these and other needs that are not met by prior art devices.